1. Field of the Invention
This invention relates to methods for the storage of plant material from guayule and guayule-like-plants prior to processing the material to recover valuable components thereof such as rubber, resin, bagasse, etc. Specifically it relates to mixing the material in communited form with organic liquid to form a slurry and storing the slurry for at least 24 hours. It also relates to the slurry thus formed.
2. General Background
There is a need for a practical convenient and effective method and system for the storage of guayule shrub prior to processing. It is clear, for example, a commercial unit designed to recover valuable guayule rubber, resin and other products from shrub will be most efficient when operating on a continuous basis. It is well known that intermittent production is costly in terms of operating expenses as well as lost production. Productivity decreases and energy costs increase if a guayule processing unit has to be shut down because of an interruption in supply of raw material.
Disruption of raw material supply might well be caused by weather conditions which prevent harvesting. The interruption of harvesting could be short or prolonged. In any event, it is clear that an adequate continuous supply of guayule raw material would increase the efficiency of a guayule processing unit.
It is also well known in industry that space requirements for raw material storage can significantly add to costs. Although storage of whole guayule shrub might be preferred because of the relatively low surface area of the shrub exposed to the atmosphere, economics are improved if the shrub is communited (ground) thus requiring less storage space than the bulky harvested shrub. In addition, the use of unground pollarded guayule shrub as a raw material interfers with transfers. The bulk handling of essentially free flowing, ground guayule shrub is greatly preferred over the handling of low density, bulky, unground, whole or pollarded guayule shrub.
Heretofore, the temporary storage of ground guayule shrub has been considered technically feasible; however, storage time has been severely limited. The storage time could be increased by storing the ground material under an inert gas; but again this is an expensive operation and, from a technical standpoint, the displacement of all oxygen from the stored shrub is very difficult, if not impossible.
In addition to the above problems of using inert gas, a very practical problem of compaction of the ground shrub by the very weight of the shrub itself is encountered. Furthermore, during the grinding of the guayule shrub, resins are released which tend to bind the ground shrub particles into agglomerates. If even a small amount of moisture is present in the shrub, simple sugars present in the shrub can also aggravate this agglomeration problem.